xref: /dragonfly/lib/libc/xdr/xdr.3 (revision a9783bc6) 
1.\" @(#)xdr.3n	2.2 88/08/03 4.0 RPCSRC; from 1.16 88/03/14 SMI
2.\" $FreeBSD: head/lib/libc/xdr/xdr.3 318712 2017-05-23 07:17:52Z ngie $
3.\"
4.Dd June 9, 2018
5.Dt XDR 3
6.Os
7.Sh NAME
8.Nm xdr ,
9.Nm xdr_array ,
10.Nm xdr_bool ,
11.Nm xdr_bytes ,
12.Nm xdr_char ,
13.Nm xdr_destroy ,
14.Nm xdr_double ,
15.Nm xdr_enum ,
16.Nm xdr_float ,
17.Nm xdr_free ,
18.Nm xdr_getpos ,
19.Nm xdr_hyper ,
20.Nm xdr_inline ,
21.Nm xdr_int ,
22.Nm xdr_int16_t ,
23.Nm xdr_int32_t ,
24.Nm xdr_int64_t ,
25.Nm xdr_long ,
26.Nm xdr_longlong_t ,
27.Nm xdrmem_create ,
28.Nm xdr_opaque ,
29.Nm xdr_pointer ,
30.Nm xdrrec_create ,
31.Nm xdrrec_endofrecord ,
32.Nm xdrrec_eof ,
33.Nm xdrrec_skiprecord ,
34.Nm xdr_reference ,
35.Nm xdr_setpos ,
36.Nm xdr_short ,
37.Nm xdr_sizeof ,
38.Nm xdrstdio_create ,
39.Nm xdr_string ,
40.Nm xdr_u_char ,
41.Nm xdr_u_hyper ,
42.Nm xdr_u_int ,
43.Nm xdr_u_long ,
44.Nm xdr_u_longlong_t ,
45.Nm xdr_uint16_t ,
46.Nm xdr_u_int16_t ,
47.Nm xdr_uint32_t ,
48.Nm xdr_u_int32_t ,
49.Nm xdr_uint64_t ,
50.Nm xdr_u_int64_t ,
51.Nm xdr_union ,
52.Nm xdr_u_short ,
53.Nm xdr_vector ,
54.Nm xdr_void ,
55.Nm xdr_wrapstring
56.Nd "library routines for external data representation"
57.Sh LIBRARY
58.Lb libc
59.Sh SYNOPSIS
60.In rpc/types.h
61.In rpc/xdr.h
62.Pp
63See
64.Sx DESCRIPTION
65for function declarations.
66.Sh DESCRIPTION
67These routines allow C programmers to describe
68arbitrary data structures in a machine-independent fashion.
69Data for remote procedure calls are transmitted using these
70routines.
71.Pp
72.Bl -tag -width indent -compact
73.It Xo
74.Ft int
75.Xc
76.It Xo
77.Fo xdr_array
78.Fa "XDR *xdrs"
79.Fa "char **arrp"
80.Fa "u_int *sizep"
81.Fa "u_int maxsize"
82.Fa "u_int elsize"
83.Fa "xdrproc_t elproc"
84.Fc
85.Xc
86.Pp
87A filter primitive that translates between variable-length
88arrays
89and their corresponding external representations.
90The
91.Fa arrp
92argument
93is the address of the pointer to the array, while
94.Fa sizep
95is the address of the element count of the array;
96this element count cannot exceed
97.Fa maxsize .
98The
99.Fa elsize
100argument
101is the
102.Ic sizeof
103each of the array's elements, and
104.Fa elproc
105is an
106.Tn XDR
107filter that translates between
108the array elements' C form, and their external
109representation.
110This routine returns one if it succeeds, zero otherwise.
111.Pp
112.It Xo
113.Ft int
114.Xc
115.It Xo
116.Fn xdr_bool "XDR *xdrs" "bool_t *bp"
117.Xc
118.Pp
119A filter primitive that translates between booleans (C
120integers)
121and their external representations.
122When encoding data, this
123filter produces values of either one or zero.
124This routine returns one if it succeeds, zero otherwise.
125.Pp
126.It Xo
127.Ft int
128.Xc
129.It Xo
130.Fn xdr_bytes "XDR *xdrs" "char **sp" "u_int *sizep" "u_int maxsize"
131.Xc
132.Pp
133A filter primitive that translates between counted byte
134strings and their external representations.
135The
136.Fa sp
137argument
138is the address of the string pointer.
139The length of the
140string is located at address
141.Fa sizep ;
142strings cannot be longer than
143.Fa maxsize .
144This routine returns one if it succeeds, zero otherwise.
145.Pp
146.It Xo
147.Ft int
148.Xc
149.It Xo
150.Fn xdr_char "XDR *xdrs" "char *cp"
151.Xc
152.Pp
153A filter primitive that translates between C characters
154and their external representations.
155This routine returns one if it succeeds, zero otherwise.
156Note: encoded characters are not packed, and occupy 4 bytes
157each.
158For arrays of characters, it is worthwhile to
159consider
160.Fn xdr_bytes ,
161.Fn xdr_opaque
162or
163.Fn xdr_string .
164.Pp
165.It Xo
166.Ft void
167.Xc
168.It Xo
169.Fn xdr_destroy "XDR *xdrs"
170.Xc
171.Pp
172A macro that invokes the destroy routine associated with the
173.Tn XDR
174stream,
175.Fa xdrs .
176Destruction usually involves freeing private data structures
177associated with the stream.
178Using
179.Fa xdrs
180after invoking
181.Fn xdr_destroy
182is undefined.
183.Pp
184.It Xo
185.Ft int
186.Xc
187.It Xo
188.Fn xdr_double "XDR *xdrs" "double *dp"
189.Xc
190.Pp
191A filter primitive that translates between C
192.Vt double
193precision numbers and their external representations.
194This routine returns one if it succeeds, zero otherwise.
195.Pp
196.It Xo
197.Ft int
198.Xc
199.It Xo
200.Fn xdr_enum "XDR *xdrs" "enum_t *ep"
201.Xc
202.Pp
203A filter primitive that translates between C
204.Vt enum Ns s
205(actually integers) and their external representations.
206This routine returns one if it succeeds, zero otherwise.
207.Pp
208.It Xo
209.Ft int
210.Xc
211.It Xo
212.Fn xdr_float "XDR *xdrs" "float *fp"
213.Xc
214.Pp
215A filter primitive that translates between C
216.Vt float Ns s
217and their external representations.
218This routine returns one if it succeeds, zero otherwise.
219.Pp
220.It Xo
221.Ft void
222.Xc
223.It Xo
224.Fn xdr_free "xdrproc_t proc" "void *objp"
225.Xc
226.Pp
227Generic freeing routine.
228The first argument is the
229.Tn XDR
230routine for the object being freed.
231The second argument
232is a pointer to the object itself.
233Note: the pointer passed
234to this routine is
235.Em not
236freed, but what it points to
237.Em is
238freed (recursively).
239.Pp
240.It Xo
241.Ft u_int
242.Xc
243.It Xo
244.Fn xdr_getpos "XDR *xdrs"
245.Xc
246.Pp
247A macro that invokes the get\-position routine
248associated with the
249.Tn XDR
250stream,
251.Fa xdrs .
252The routine returns an unsigned integer,
253which indicates the position of the
254.Tn XDR
255byte stream.
256A desirable feature of
257.Tn XDR
258streams is that simple arithmetic works with this number,
259although the
260.Tn XDR
261stream instances need not guarantee this.
262.Pp
263.It Xo
264.Ft int
265.Xc
266.It Xo
267.Fn xdr_hyper "XDR *xdrs" "quad_t *llp"
268.Xc
269A filter primitive that translates between ANSI C
270.Vt "long long"
271integers and their external representations.
272This routine returns one if it succeeds, zero otherwise.
273.Pp
274.It Xo
275.Ft "long *"
276.Xc
277.It Xo
278.Fn xdr_inline "XDR *xdrs" "int len"
279.Xc
280.Pp
281A macro that invokes the in-line routine associated with the
282.Tn XDR
283stream,
284.Fa xdrs .
285The routine returns a pointer
286to a contiguous piece of the stream's buffer;
287.Fa len
288is the byte length of the desired buffer.
289Note: pointer is cast to
290.Vt "long *" .
291.Pp
292Warning:
293.Fn xdr_inline
294may return
295.Dv NULL
296(0)
297if it cannot allocate a contiguous piece of a buffer.
298Therefore the behavior may vary among stream instances;
299it exists for the sake of efficiency.
300.Pp
301.It Xo
302.Ft int
303.Xc
304.It Xo
305.Fn xdr_int "XDR *xdrs" "int *ip"
306.Xc
307.Pp
308A filter primitive that translates between C integers
309and their external representations.
310This routine returns one if it succeeds, zero otherwise.
311.Pp
312.It Xo
313.Ft int
314.Xc
315.It Xo
316.Fn xdr_int16_t "XDR *xdrs" "int16_t *llp"
317.Xc
318A filter primitive that translates between ANSI C
319.Vt int16_t
320integers and their external representations.
321This routine returns one if it succeeds, zero otherwise.
322.Pp
323.It Xo
324.Ft int
325.Xc
326.It Xo
327.Fn xdr_int32_t "XDR *xdrs" "int32_t *llp"
328.Xc
329A filter primitive that translates between ANSI C
330.Vt int32_t
331integers and their external representations.
332This routine returns one if it succeeds, zero otherwise.
333.Pp
334.It Xo
335.Ft int
336.Xc
337.It Xo
338.Fn xdr_int64_t "XDR *xdrs" "int64_t *llp"
339.Xc
340A filter primitive that translates between ANSI C
341.Vt int64_t
342integers and their external representations.
343This routine returns one if it succeeds, zero otherwise.
344.Pp
345.It Xo
346.Ft int
347.Xc
348.It Xo
349.Fn xdr_long "XDR *xdrs" "long *lp"
350.Xc
351.Pp
352A filter primitive that translates between C
353.Vt long
354integers and their external representations.
355This routine returns one if it succeeds, zero otherwise.
356.Pp
357.It Xo
358.Ft int
359.Xc
360.It Xo
361.Fn xdr_longlong_t "XDR *xdrs" "quad_t *llp"
362.Xc
363A filter primitive that translates between ANSI C
364.Vt "long long"
365integers and their external representations.
366This routine returns one if it succeeds, zero otherwise.
367.Pp
368.It Xo
369.Ft void
370.Xc
371.It Xo
372.Fn xdrmem_create "XDR *xdrs" "char *addr" "u_int size" "enum xdr_op op"
373.Xc
374.Pp
375This routine initializes the
376.Tn XDR
377stream object pointed to by
378.Fa xdrs .
379The stream's data is written to, or read from,
380a chunk of memory at location
381.Fa addr
382whose length is no more than
383.Fa size
384bytes long.
385The
386.Fa op
387argument
388determines the direction of the
389.Tn XDR
390stream
391(either
392.Dv XDR_ENCODE ,
393.Dv XDR_DECODE ,
394or
395.Dv XDR_FREE ) .
396.Pp
397.It Xo
398.Ft int
399.Xc
400.It Xo
401.Fn xdr_opaque "XDR *xdrs" "char *cp" "u_int cnt"
402.Xc
403.Pp
404A filter primitive that translates between fixed size opaque
405data
406and its external representation.
407The
408.Fa cp
409argument
410is the address of the opaque object, and
411.Fa cnt
412is its size in bytes.
413This routine returns one if it succeeds, zero otherwise.
414.Pp
415.It Xo
416.Ft int
417.Xc
418.It Xo
419.Fn xdr_pointer "XDR *xdrs" "char **objpp" "u_int objsize" "xdrproc_t xdrobj"
420.Xc
421.Pp
422Like
423.Fn xdr_reference
424except that it serializes
425.Dv NULL
426pointers, whereas
427.Fn xdr_reference
428does not.
429Thus,
430.Fn xdr_pointer
431can represent
432recursive data structures, such as binary trees or
433linked lists.
434.Pp
435.It Xo
436.Ft void
437.Xc
438.It Xo
439.Fo xdrrec_create
440.Fa "XDR *xdrs"
441.Fa "u_int sendsize"
442.Fa "u_int recvsize"
443.Fa "void *handle"
444.Fa "int \*(lp*readit\*(rp\*(lp\*(rp"
445.Fa "int \*(lp*writeit\*(rp\*(lp\*(rp"
446.Fc
447.Xc
448.Pp
449This routine initializes the
450.Tn XDR
451stream object pointed to by
452.Fa xdrs .
453The stream's data is written to a buffer of size
454.Fa sendsize ;
455a value of zero indicates the system should use a suitable
456default.
457The stream's data is read from a buffer of size
458.Fa recvsize ;
459it too can be set to a suitable default by passing a zero
460value.
461When a stream's output buffer is full,
462.Fn writeit
463is called.
464Similarly, when a stream's input buffer is empty,
465.Fn readit
466is called.
467The behavior of these two routines is similar to
468the
469system calls
470.Xr read 2
471and
472.Xr write 2 ,
473except that
474.Fa handle
475is passed to the former routines as the first argument.
476Note: the
477.Tn XDR
478stream's
479.Fa op
480field must be set by the caller.
481.Pp
482Warning: this
483.Tn XDR
484stream implements an intermediate record stream.
485Therefore there are additional bytes in the stream
486to provide record boundary information.
487.Pp
488.It Xo
489.Ft int
490.Xc
491.It Xo
492.Fn xdrrec_endofrecord "XDR *xdrs" "int sendnow"
493.Xc
494.Pp
495This routine can be invoked only on
496streams created by
497.Fn xdrrec_create .
498The data in the output buffer is marked as a completed
499record,
500and the output buffer is optionally written out if
501.Fa sendnow
502is non-zero.
503This routine returns one if it succeeds, zero
504otherwise.
505.Pp
506.It Xo
507.Ft int
508.Xc
509.It Xo
510.Fn xdrrec_eof "XDR *xdrs"
511.Xc
512.Pp
513This routine can be invoked only on
514streams created by
515.Fn xdrrec_create .
516After consuming the rest of the current record in the stream,
517this routine returns one if the stream has no more input,
518zero otherwise.
519.Pp
520.It Xo
521.Ft int
522.Xc
523.It Xo
524.Fn xdrrec_skiprecord "XDR *xdrs"
525.Xc
526.Pp
527This routine can be invoked only on
528streams created by
529.Fn xdrrec_create .
530It tells the
531.Tn XDR
532implementation that the rest of the current record
533in the stream's input buffer should be discarded.
534This routine returns one if it succeeds, zero otherwise.
535.Pp
536.It Xo
537.Ft int
538.Xc
539.It Xo
540.Fn xdr_reference "XDR *xdrs" "char **pp" "u_int size" "xdrproc_t proc"
541.Xc
542.Pp
543A primitive that provides pointer chasing within structures.
544The
545.Fa pp
546argument
547is the address of the pointer;
548.Fa size
549is the
550.Ic sizeof
551the structure that
552.Fa *pp
553points to; and
554.Fa proc
555is an
556.Tn XDR
557procedure that filters the structure
558between its C form and its external representation.
559This routine returns one if it succeeds, zero otherwise.
560.Pp
561Warning: this routine does not understand
562.Dv NULL
563pointers.
564Use
565.Fn xdr_pointer
566instead.
567.Pp
568.It Xo
569.Ft int
570.Xc
571.It Xo
572.Fn xdr_setpos "XDR *xdrs" "u_int pos"
573.Xc
574.Pp
575A macro that invokes the set position routine associated with
576the
577.Tn XDR
578stream
579.Fa xdrs .
580The
581.Fa pos
582argument
583is a position value obtained from
584.Fn xdr_getpos .
585This routine returns one if the
586.Tn XDR
587stream could be repositioned,
588and zero otherwise.
589.Pp
590Warning: it is difficult to reposition some types of
591.Tn XDR
592streams, so this routine may fail with one
593type of stream and succeed with another.
594.Pp
595.It Xo
596.Ft int
597.Xc
598.It Xo
599.Fn xdr_short "XDR *xdrs" "short *sp"
600.Xc
601.Pp
602A filter primitive that translates between C
603.Vt short
604integers and their external representations.
605This routine returns one if it succeeds, zero otherwise.
606.Pp
607.It Xo
608.Ft unsigned long
609.Xc
610.It Xo
611.Fn xdr_sizeof "xdrproc_t func" "void *data"
612.Xc
613.Pp
614This routine returns the amount of memory required to encode
615.Fa data
616using filter
617.Fa func .
618.Pp
619.It Li "#ifdef _STDIO_H_"
620.It Li "/* XDR using stdio library */"
621.It Xo
622.Ft void
623.Xc
624.It Xo
625.Fn xdrstdio_create "XDR *xdrs" "FILE *file" "enum xdr_op op"
626.Xc
627.It Li "#endif"
628.Pp
629This routine initializes the
630.Tn XDR
631stream object pointed to by
632.Fa xdrs .
633The
634.Tn XDR
635stream data is written to, or read from, the Standard
636.Tn I/O
637stream
638.Fa file .
639The
640.Fa op
641argument
642determines the direction of the
643.Tn XDR
644stream (either
645.Dv XDR_ENCODE ,
646.Dv XDR_DECODE ,
647or
648.Dv XDR_FREE ) .
649.Pp
650Warning: the destroy routine associated with such
651.Tn XDR
652streams calls
653.Xr fflush 3
654on the
655.Fa file
656stream, but never
657.Xr fclose 3 .
658.Pp
659.It Xo
660.Ft int
661.Xc
662.It Xo
663.Fn xdr_string "XDR *xdrs" "char **sp" "u_int maxsize"
664.Xc
665.Pp
666A filter primitive that translates between C strings and
667their
668corresponding external representations.
669Strings cannot be longer than
670.Fa maxsize .
671Note:
672.Fa sp
673is the address of the string's pointer.
674This routine returns one if it succeeds, zero otherwise.
675.Pp
676.It Xo
677.Ft int
678.Xc
679.It Xo
680.Fn xdr_u_char "XDR *xdrs" "unsigned char *ucp"
681.Xc
682.Pp
683A filter primitive that translates between
684.Vt unsigned
685C characters and their external representations.
686This routine returns one if it succeeds, zero otherwise.
687.Pp
688.It Xo
689.Ft int
690.Xc
691.It Xo
692.Fn xdr_u_hyper "XDR *xdrs" "u_quad_t *ullp"
693.Xc
694A filter primitive that translates between
695.Vt unsigned
696ANSI C
697.Vt long long
698integers and their external representations.
699This routine returns one if it succeeds, zero otherwise.
700.Pp
701.It Xo
702.Ft int
703.Xc
704.It Xo
705.Fn xdr_u_int "XDR *xdrs" "unsigned *up"
706.Xc
707.Pp
708A filter primitive that translates between C
709.Vt unsigned
710integers and their external representations.
711This routine returns one if it succeeds, zero otherwise.
712.Pp
713.It Xo
714.Ft int
715.Xc
716.It Xo
717.Fn xdr_uint16_t "XDR *xdrs" "uint16_t *llp"
718.Xc
719.It Xo
720.Ft int
721.Xc
722.It Xo
723.Fn xdr_u_int16_t "XDR *xdrs" "uint16_t *llp"
724.Xc
725Filter primitives that translate between C
726.Vt uint16_t
727integers and their external representations.
728These routines return one if they succeed, zero otherwise.
729.Pp
730.It Xo
731.Ft int
732.Xc
733.It Xo
734.Fn xdr_uint32_t "XDR *xdrs" "uint32_t *llp"
735.Xc
736.It Xo
737.Ft int
738.Xc
739.It Xo
740.Fn xdr_u_int32_t "XDR *xdrs" "uint32_t *llp"
741.Xc
742Filter primitives that translate between C
743.Vt uint32_t
744integers and their external representations.
745These routines return one if they succeed, zero otherwise.
746.Pp
747.It Xo
748.Ft int
749.Xc
750.It Xo
751.Fn xdr_uint64_t "XDR *xdrs" "uint64_t *llp"
752.Xc
753.It Xo
754.Ft int
755.Xc
756.It Xo
757.Fn xdr_u_int64_t "XDR *xdrs" "uint64_t *llp"
758.Xc
759Filter primitives that translate between C
760.Vt uint64_t
761integers and their external representations.
762These routines return one if they succeed, zero otherwise.
763.Pp
764.It Xo
765.Ft int
766.Xc
767.It Xo
768.Fn xdr_u_long "XDR *xdrs" "unsigned long *ulp"
769.Xc
770.Pp
771A filter primitive that translates between C
772.Vt "unsigned long"
773integers and their external representations.
774This routine returns one if it succeeds, zero otherwise.
775.Pp
776.It Xo
777.Ft int
778.Xc
779.It Xo
780.Fn xdr_u_longlong_t "XDR *xdrs" "u_quad_t *ullp"
781.Xc
782A filter primitive that translates between
783.Vt unsigned
784ANSI C
785.Vt "long long"
786integers and their external representations.
787This routine returns one if it succeeds, zero otherwise.
788.Pp
789.It Xo
790.Ft int
791.Xc
792.It Xo
793.Fn xdr_u_int64_t "XDR *xdrs" "uint64_t *llp"
794.Xc
795A filter primitive that translates between C
796.Vt uint64_t
797integers and their external representations.
798This routine returns one if it succeeds, zero otherwise.
799.Pp
800.It Xo
801.Ft int
802.Xc
803.It Xo
804.Fn xdr_u_short "XDR *xdrs" "unsigned short *usp"
805.Xc
806.Pp
807A filter primitive that translates between C
808.Vt "unsigned short"
809integers and their external representations.
810This routine returns one if it succeeds, zero otherwise.
811.Pp
812.It Xo
813.Ft int
814.Xc
815.It Xo
816.Fo xdr_union
817.Fa "XDR *xdrs"
818.Fa "enum_t *dscmp"
819.Fa "char *unp"
820.Fa "const struct xdr_discrim *choices"
821.Fa "xdrproc_t defaultarm"
822.Fc
823.Xc
824.Pp
825A filter primitive that translates between a discriminated C
826.Vt union
827and its corresponding external representation.
828It first
829translates the discriminant of the union located at
830.Fa dscmp .
831This discriminant is always an
832.Vt enum_t .
833Next the union located at
834.Fa unp
835is translated.
836The
837.Fa choices
838argument
839is a pointer to an array of
840.Vt xdr_discrim
841structures.
842Each structure contains an ordered pair of
843.Bq Va value , proc .
844If the union's discriminant is equal to the associated
845.Va value ,
846then the
847.Fn proc
848is called to translate the union.
849The end of the
850.Vt xdr_discrim
851structure array is denoted by a routine of value
852.Dv NULL .
853If the discriminant is not found in the
854.Fa choices
855array, then the
856.Fn defaultarm
857procedure is called (if it is not
858.Dv NULL ) .
859Returns one if it succeeds, zero otherwise.
860.Pp
861.It Xo
862.Ft int
863.Xc
864.It Xo
865.Fo xdr_vector
866.Fa "XDR *xdrs"
867.Fa "char *arrp"
868.Fa "u_int size"
869.Fa "u_int elsize"
870.Fa "xdrproc_t elproc"
871.Fc
872.Xc
873.Pp
874A filter primitive that translates between fixed-length
875arrays
876and their corresponding external representations.
877The
878.Fa arrp
879argument
880is the address of the pointer to the array, while
881.Fa size
882is the element count of the array.
883The
884.Fa elsize
885argument
886is the
887.Ic sizeof
888each of the array's elements, and
889.Fa elproc
890is an
891.Tn XDR
892filter that translates between
893the array elements' C form, and their external
894representation.
895This routine returns one if it succeeds, zero otherwise.
896.Pp
897.It Xo
898.Ft int
899.Xc
900.It Xo
901.Fn xdr_void void
902.Xc
903.Pp
904This routine always returns one.
905It may be passed to
906.Tn RPC
907routines that require a function argument,
908where nothing is to be done.
909.Pp
910.It Xo
911.Ft int
912.Xc
913.It Xo
914.Fn xdr_wrapstring "XDR *xdrs" "char **sp"
915.Xc
916.Pp
917A primitive that calls
918.Fn xdr_string xdrs sp MAXUN.UNSIGNED ;
919where
920.Dv MAXUN.UNSIGNED
921is the maximum value of an unsigned integer.
922The
923.Fn xdr_wrapstring
924function
925is handy because the
926.Tn RPC
927package passes a maximum of two
928.Tn XDR
929routines as arguments, and
930.Fn xdr_string ,
931one of the most frequently used primitives, requires three.
932Returns one if it succeeds, zero otherwise.
933.El
934.Sh SEE ALSO
935.Xr rpc 3
936.Rs
937.%T "eXternal Data Representation Standard: Protocol Specification"
938.Re
939.Rs
940.%T "eXternal Data Representation: Sun Technical Notes"
941.Re
942.Rs
943.%T "XDR: External Data Representation Standard"
944.%O RFC 1014
945.%Q "Sun Microsystems, Inc., USC\-ISI"
946.Re
947.Sh HISTORY
948The
949.Nm xdr_sizeof
950function first appeared in
951.Fx 9.0 .
952